This application is based on Japanese Patent Application Nos. 2001-078655 filed Mar. 19, 2001 and 2002-048638 filed Feb. 25, 2002, the contents of which are incorporated hereinto by reference.
1. Field of the Invention
The present invention relates to an open top IC socket for mounting a grid array IC package such as a BGA (Ball Grid Array), a CSP (Clip Scale Package) or a PGA (Pin Grid Array), and more particularly relates to an open top IC socket capable of attaching or detaching of a plurality of IC packages simultaneously with one operation.
2. Description of the Related Art
Upon a manufactured IC package being tested on its performance, an IC socket is interposed between an inspection board and the IC package, which IC package is thereupon adapted to be rapidly exchangeable with respect to the IC socket. A prior art open top IC socket that mounts a grid array type IC package mounts in general only one IC package thereon.
Referring to FIG. 9, such a prior art open top IC socket is illustrated in a plane view, and to FIG. 10, illustrated in a front view. The IC socket 100 comprises a socket body 101, a slide block 103 that is superimposed on the socket body 101 and includes a plurality of lines of elongated terminal insertion holes 102, into which holes pin terminals or ball like terminals formed on an IC package (not shown) are inserted, two sets of operation levers 104 and 105 for laterally moving the slide block 103 along the surface of the socket body 101, and an operation member 106 for operating these operation levers 104 and 105 by depression.
The IC socket 100 further includes a plurality of connector pins each for electrically connecting the mounted IC package and an inspection board (not shown) for inspecting the IC package. The plurality of the connector pins include a plurality of paired contact sections 107 located in the terminal insertion holes 102 for holding the terminal of the IC package, and a plurality of terminal sections 108 protruded from the socket body 101 and inserted into the inspection board. The contact section 107 is adapted such that its one side engages with the slide block 103 in the terminal insertion hole 103 and it is hereby made resiliently displaceable in the direction opposite to the other side following a lateral movement of the slide block 103.
When the IC package is mounted on the IC socket 100, a guide piece 109 formed on the operation member 106 is depressed along the guide groove 110 mechanically or manually. Pressure reception sections 111 of the operation levers 104 and 105 receive the depressing operation whereby the operation levers 104 and 105 are rotated around a lever support shaft 112 provided on the socket body 101.
Owing to the rotation motion of the operation levers 104 and 105, the slide block 103 undergoes a lateral movement in the right direction in FIG. 9 through a transmission shaft 113 against spring force provided with the contact section 107 itself. The contact section 107 of each pair is hereby opened as illustrated in FIG. 9. The IC package is positioned with respect to the slide block 103 while being guided by a guide section 114 protruded at four corners of the slide block 103, whereby terminals of the IC package go in between the contact sections 107 of the corresponding pair.
When the depressing force to the operation member 106 is released in this situation, the operation member 106 returns to the original rise end position owing to the spring force provided with the contact section 107 itself. Following this, the slide block 103 also returns to the initial position. The terminal of the IC package is thus held between the corresponding contact section 107.
When the IC package is detached from the IC socket 100, the operation member 106 is again depressed to force the slide block 103 to undergo a lateral movement through the operation levers 104 and 105 and hence open the contact sections 107 of each pair for release of the restriction of the contact sections 107 for the terminals of the IC package. Thereafter, the IC package is pulled out from the IC socket 100, whereby the IC package is detached from the IC socket 100 with ease.
Details of the opening/closing operation of the contact section 107 are disclosed in Japanese Patent Application Laid-Open No. 4-19979 (1992), etc., for example.
The prior art IC socket 100 in the type illustrated in FIGS. 9 and 10 simply mounts only one IC package for the one IC socket. This causes a difficulty that provided the IC packages are different from each other in their types, IC sockets corresponding to those types are required.
A recent trend that the number of IC packages to be checked is increased requires a need of inspecting many types of IC packages. An increase of the number of IC packages to be inspected causes a difficulty that a packaged area of the prior art IC socket is severely increased when an IC socket is mounted on an inspection board, particularly only one IC package can be mounted. There is sharply increased the time required for attaching and detaching of an IC package by manual.
It is therefore an object of the present invention to provide an open top IC socket wherein packaging density is high, and a plurality of IC packages can be simultaneously attached or detached and hence the manufacturing cost is reduced.
An open top IC socket according to the present invention is adapted such that a slide block on which an IC package is mounted and a socket body are individually brought into units, and a socket base and a slide block movement mechanism, etc., all being capable of being shared, are unified. Namely, the open top IC socket according to the present invention comprises:
a plurality of IC package mounting units each including a socket body that includes a plurality of pairs of contact sections into which terminals of an IC package are inserted and each of which is able to open and close, and each further including a slide block slidably overlapped on the socket body for opening and closing the plurality of pairs of the contact sections;
a socket base for containing and holding the IC package mounting units in an aligned state;
a coupling member for mutually coupling the individual slide blocks of the IC package mounting units; and
block operation means mounted on the socket base for sliding the individual slide blocks in the direction of sliding of the slide blocks.
When an IC package is mounted in the present invention, the block operation means is operated to slide the plurality of the slide blocks simultaneously and hence change over the contact section of each socket body to an open state. Then, after the terminal of each IC package is inserted between the opened contact sections of the corresponding socket body, the block operation means is returned to the original position to slide the plurality of the slide blocks simultaneously and hence change over the contact section of the individual socket body. Hereby, the individual terminal is held by the contact sections of the corresponding pair to establish electrical connection.
When the IC package is detached from such a connecting situation, the block operation means is again operated to slide the plurality of the slide blocks simultaneously and hence change over the contact section of the individual socket body to an open state. Hereby, restriction of the contact section to the terminal of the IC package is released, whereby the individual IC package is drawn out from the corresponding individual socket body.
In accordance with the present invention, a plurality of the IC package mounting units are assembled in one socket base, so that the size of an external appearance is more reduced than the case where a plurality of the prior art IC sockets are simply incorporated to ensure light weight thereof and reduction of the number of parts and hence reduce the manufacturing cost thereof. Further, packaging density of the IC socket with respect to the inspection board is substantially increased, so that the number of IC packages capable of being inspected is substantially increased, so that the number of IC packages capable of being inspected at a time can be set higher.
In the open top IC socket according to the present invention, the socket base may include a plurality of engaging means engaged with the individual socket bodies of the IC package mounting units for locking the socket bodies to the socket base. In case of these plurality of engaging means have a resiliently deformable locking pawl, the socket body can be securely locked to the socket base. In particular, when the plurality of engaging means have a resiliently deformable locking pawl, an exchange of the IC package mounting unit to the socket base is ensured, and the unit can be exchanged to an IC package mounting unit corresponding to the type of an IC package that is an inspection object for applications of general purposes.
The coupling member may be slidably mounted on the socket base in parallel to the direction of the sliding of the slide block. In this situation, a mechanism for sliding in a lump all slide blocks can be more simplified.
The block operation member may include an operation lever which is mounted on the socket base and to which the coupling member is coupled. In this situation, sliding of all slide blocks can be achieved with ease only by operation of the operation lever.
The each socket body of the IC package mounting units may further include a plurality of terminals each of which is protruded from the socket body and is conductive with the plurality of pairs of the contacts. In this case, the plurality of the terminals may be inserted into the plurality of pairs of contacts formed on an inspection board for inspecting an IC package. In this situation, the open top IC socket is useable for the inspection board for inspecting an IC package.
The above and other objects, effects, features and advantages of the present invention will become more apparent from the following description of embodiments thereof taken in conjunction with the accompanying drawings.